1. Field of the Invention
The present invention relates to an electrical generator, and more particularly to an electrical generator with a coil and a set of magnets that are separated from each other.
2. Description of Related Art
Electrical generators convert mechanical energy to electricity. A conventional generator includes a stator and a rotor. The stator has a frame and a winding. The frame has an inner space defined longitudinally and the winding is mounted in the frame around the inner space. The winding is made of conductive wire so the winding will conduct a current.
The rotor includes a set of permanent magnets and an armature. The set of permanent magnets has north and south poles alternately mounted circumferentially on the armature. When the generator is assembled, the armature is rotatably mounted in the inner space in the stator, and the set of permanent magnets is positioned corresponding to the winding. A gap exists between the set of permanent magnets and the winding. A bearing is attached to the armature at a side of the set of permanent magnets respectively to hold the armature and allow it to rotate relative to the stator.
When the armature is coupled to a prime mover such as a water turbine, the water turbine rotates the armature, and the set of permanent magnets is rotated by the armature relative to the winding in the stator. The rotating set of permanent magnets induces an electromotive force in the winding.
However, conventional generators still has some shortcomings that include:
1. Proper alignment of the rotor and the stator is critical, which may make assembly difficult.
Because the rotor rotates at a very high speed inside the stator, the armature of the rotor must be precisely positioned to ensure that the rotor does not contact the stator during operation of the generator. The assembly of the rotor and the stator is made more difficult because two bearings are required to carry the weight of the armature.
2. Manufacturing costs are high.
The precise positioning of the rotor and the stator require complicated processes and equipment that directly result in increased manufacturing costs.
To overcome the shortcomings, the present invention provides an electrical generator with a separate coil and magnet set to mitigate or obviate the aforementioned problems.
The main objective of the invention is to reduce costs and time to manufacture an electrical generator.
Other advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.